This episode contributes heavily to the 'Klingon forehead problem' - by showing that Klingons who had smooth foreheads in the original series now have the bumpy look, it rules out the idea that some evolutionary or other cross-generational factor could be responsible for this change.

Plotline

Dax must decide whether to honour a blood oath made by Curzon when three Klingon warriors arrive on the station hunting an old enemy.